Pull rod pump jack



Nov. 30 1926. 1,609,250

J. H. HOLMGREEN PULL ROD PUMP JACK Filed Sept. 23, 1924 3 Sheets-Sheet 1 Nov. 30 1926.

J. H. HOLMGREEN PULL ROD PUMP JACK Filed Sept. 25 1924 S Sheets-Sheet 2 Ewen/for: Juzowfl okgre en,

Nov. 30, 1926. 1,609,250 J. H. HOLMGRE EN PULL ROD PUMP JACK Filed Sept. 25, 1924 3 Sheets-Sheet 5 Irwezwfir: Julius flfz'blnglreezv,

Patented Nov. 30, 1926.

UNITED sTTEs JULIUS H. HOLMGREEN, OF SAN ANTONIO, TEXAS. I

PULL non :PUMP JACK.

My said invention relates to a pull-rod pump jack of the type commonly used 1n o 1l fields for pumping oil and water, and 1t 1s an object of the invention to translate the oscillatin motion of the walking beam mto a perpendicular reciprocation of the pump rod without ,any bending or twlstlng straln on the pump rod or the connecting parts.

Referring to the accompanymg drawlngs, which are made a part hereof and on WhlCh similar reference characters indicate similar arts: p Figure 1 is a side elevation of my device;

Figure 2 an end view looking toward the right in Figure 1;

I Figure 3 a fragmentary v1ew of parts seen in Figure 1 on an enlarged scale;

Figure 4 a detail of a sprocket cam which is a feature of the invention;

Figure 5 an end view of the same;

Figure 6' an end view of the machine shown in Figure 1 looking toward the left;

Figure 7 a section on line 77' of Figure 1 looking towardthe right; and i Figure 8 a'detail on an enlarged scale of a yoke shown in Figure 1.

The device of my invention comprises a base '10 preferably built up of structural iron and mounted on a suitable foundation. A fixed rigid frame rises fromthe base, said frame including rear posts 11 connected by across-braces 11' as usual. The posts carry a walking beam 12 pivoted 1t 13 to said posts by means of a yoke block 13' fitting between the posts and the side bars of the walking beam and fixed t0 the latter. Another pair of posts 14 are rigidly fixed. to the base in any conventional or desirable manner said posts being united at their upper end to form a guide for the walking beam and being rigidly secured to the first named postby one or more horizontal bolts 15. In the preferred embodiment of the invention shown in Figures 1 and 7 these parts are formed out of an I-beam split at the lower end to provide T-shaped forks riveted to the channel bars forming the side members of the base. A pair of diagonal braces 16 preferably comprising pipes flattened at the ends are each secured at one end to one of the posts 11 at the upper rear corner of the rigid frame and at their lower ends to on the base there is a pivot 17 journaled in of the Application filed September 23, 1924. Serial No. 739,410.

bearings 18.fixed to the side bars of the base. The pivot supports the, rocking lever 19 of the Oklahoma jack type on which, is an upright 20 adjacent the middle of the lever bearing at its upper end a yoke-block 21 having a plurality of notches to receive a yoke 22 to which the pull rod 23 is attached by a hook 24. The upright 20 is braced and held in place by diagonal bars 25 and 26. A Weight box 27 at one end of the lever serves to counterbalance the weight ump rod and other reciprocating parts w ich falls on the other end of the lever, said lever being extended rearwardly for this purpose.

At the forward end of the lever there is a bearing 28 supporting the rounded lower end of a connecting rod 29 (or a casting on said rod) and providing a hinge-joint or a ball-and-socket joint as preferred between the members referred to. At its upper end the rod 29 is forked to embrace the walking beam and the forks are pivoted by a shaft 30 to a pair of split bearings 31 sitting on the channel irons which constitute the side members of the walking beam 12. I

A sprocket cam 32 which is a leading feature of my invention has a hub with shoul- 31 on the walking beam and said hub has extensions 33 journaled in said boxes. The.

extensions of the hub abut against the forks of connecting rod 29 and the parts are held together by pins 34 passing through the ends of pivot shaft 30 and the forks 31 of the yoke on the connecting rod. By this construction the cam sprocket is heldsecurely against endwise movement, but can rotate freely in its bearings'31, while shaft 30 has only a slight rocking movement imparted by rod 29. Bolts 35 hold the top of the split hearings in place. a

The cam 32 is flattened at one side of the periphery as hereinafter explained to provide for the desired cam action. A sprocket chain 36 passes over said sprocket cam 32 and is secured at one end to the pump rod 37 by adjustable connecting means as indicated at 38. At the other end the chain is connected to ,a yoke 39 pivoted at 40 toa cross bar 41 fixed to the channel bars forming the side members of the base and serving with the cross-bar 18 and such other braces as may be needed, to hold the parts of the base together. The means for attaching the chain to the yoke includes a bolt 42, secured to or integral with a block 43 bolted to side links of the chain, and nuts 44 connecting the bolt adjustably to the yoke.

In the operation of my device the pull rod is actuated from a central point as is customary in the well known distant-pumping systems causing the lever 19 to rock on its pivot 17 and move the connecting rod 29 up and down whereby also the walking beam 12 is caused to oscillate or reciprocate about its fixed pivot 13. Since the frame including the posts is rigid and the pivot 13 is rigidly fixed in relation to the remainder of the device the free end of the walking beam necessarily moves in the arc of the circle and unless some. provision to remedy the defect is made the upper end of the pump rod above the well casing 40 willbe caused to bend or flex to and fro with the movement of the walking beam up and down, which is detrimental to the pump rod and its connections to the walking beam. To prevent such action the sprocket cam is mounted on a fixed pivot adjacent the outer end of the walking beam and is provided with teeth 46 of a size adapted to engage between the rollers or other cross-members of the sprocket chain. The sprocket cam as will be evident from Figure 4 has a part at the right hand side of said figure which is a semi-circumference struck on the axis of the cam as a center, while the remainder of the periphery is som ewhat flattened. The shortest radius is in dieated at a and the radius increases through 6, 0, (Z, 6, or through Z), 0', cl, e, until it coincides with the radius of the circle on which the semi-circumference is formed.

The cam is so mounted on the walking beam that the radius a is horizontal whenthe walking beam is horizontal. When the cam has reached the position indicated in dotted lines at 42 the radius ewill be horizontal, that is to say, the sprocket cam will have turned gradually so as to gradually increase the efi'ective length of the walking beam and maintain the point of contact between the sprocket and the chain in such a position as to move the pump rod 34 in a straight line perpendicularly without bending it, the portion of the chain between the cam and the pump rod also remaining perpendicular and parallel to the pump rod. As the walking beam moves downward the sprocket cam will be forced to rotate by the weight of the pumping devices and pump rod pulling down on the chain and will pass through the full-line position of Figure 3 into the lower dotted line position at 43 where the radius 6 will be horizontal, thereby again elongating the effective length of the walking beam to move the pump-rod perpendicularly without distorting it or the chain connecting it to the sprocket cam.

In order to give a long stroke to the pump rod the chain passes over the eccentric cam to the yoke 36 to which it is attached at the upper end of the yoke thereby doubling the normal stroke of the pump rod and giving ita movement greatly in excess of the movement of the pull rod 23. The pivotal conncction of the yoke to the base permits the yoke to swing suliiciently to allow for the arcuate movement of the inner side of the eccentric cam as the walking beam moves up and down and thereby avoids any unnecessarystrain on the chain and the yoke. It will be obvious to those skilled in the art that changes maybe made in my device without departing from the spirit of the invention and therefore I do not limit myself to the: precise construction shown in the drawings and described in the specification but only as indicated in the appended claims.

It will be apparent also that my invention does away with all of the complicated and wobbly combinations of links, levers, etc., heretofore used to change an oscillatory movement into a true rectilinear movement, reliance being had solely on the sprocket cam to compensate for the arcuate movement of the end of the walking beam and trans-- mit an accurate perpendicular movement to the pump-rod, thereby avoiding all bending strains on said rod and its connections and also doing away with excessive wear on the bearings of the rod and the connecting de; vices therefor, due to sidewise pull on the rod.

The long stroke mechanism is a valuable feature of the invention, greatly increasing the capacity of the pump, and is had by the use of very simple inexpensive and effective means.

In pumping jacks as hitherto constructed the beam at the point of attachment to the pump rod describes an arcuate path, and the rod must follow such arc, whereby it is con-v tinually subjected to lateral stresses, and undesirable wear and strain on the stufiing box and other parts of the mechanism results. It is therefore my purpose in carrying out this invention to provide a pumping jack wherein the rod will traverse a rectilinear path and the effective length of the beam will be varied during its movement so as to maintain the force exerted to lift the pump rod always in line with the entire rod whereby the rod and the connection from the rod to the walking beam traverse an undeviating path.

Having thus fully described my said invention what I claim is:

1. In a pull-rod pumping jack, a walking-beam and means cooperating therewith to produce a pump-rod stroke of double the normal length comprising a sprocket cam rotatably mounted at one endof the walkingbeam and. a sprocket chain passing over the sprocket cam said chain being adjustably secured at one end to a fixed supportkand as set forth.

2. In a pull-rod pumping jack, a walkingbeam and means cooperating therewith to produce a pump-rod stroke in excess of the stroke of the pull-rod comprising a sprocket cam rotatably mounted at one end of the walking-beam and a sprocket chain passing over the Sprocket cam said chain being adjustably secured at one end to a fixed support and at the other to the pump-rod, substantially as set forth.

3. In a pull-rod pumping-jack, a walking beam, a sprocket cam rotatably mounted at one end thereof, a sprocket chain attached atone end to the pull-rod and at the other end to a fixed support below the walking beam said chain passing over the'sprocket cam, substantially as set forth- 4. Means for connecting oscillatory motion into right-line reciprocation comprising a walking beam, a reciprocating rod adjacent one'end thereof, a flexible connection between the'rod and the walking beam, and a rotary cam'on the walking beam engaging said connection and serving to hold said connection in line with the rod, substantially as set forth. I

5. In a pull-rod pump jack, a walking beam, a, rotary cam at one end thereof, a flexible connection passing from the pump rod over the cam and means for rotating the cam in timed relation with the movement of the walking beam to maintain the flexible connection in perpendicular position, substantially as set forth.

6. In a device for changing oscillatory motion into rectilinear motion, a bar swinging on a fixed center, a device movable in a straight line, a cam on the bar movable on a fixed axis, a flexible connection from said device to said cam, and means for moving thec'am 1n fixed relation to the movement as set forth.

7. In a device for changing oscillatory motion into rectilinear motion, a, bar swing timed relation to the movement of the bar the cam being so positioned that the direction of the pull on the pum rod remains constant, substantially as set orth. 8. In a pull-rod pump-jack, a walking beam, a fixed pivot therefor, a connecting rod having a yoke embracing the front end of the walking beam, and pivoted thereto, a cam on the pivot, sprocket teeth on the cam, a sprocket chain passing over the sprocket cam, means at one end of said cam attachment to a pump-rod, and a pivotal connection at the other end to the fixed base of the 1 cess of that of the pull-rod including a chain "passing over the sprocket cam said chain being connected at one end to the pumprod and at the other to a fixed support below "the walking beam, substantially as set forth.

11. In a pull-rod pumping-jack, a walking beam, a sprocket cam rotatably mounted at one end thereof, a sprocket chain having means for attachment at one end to a pump rod and at the other end to a support below the walking beam said chain passing over the sprocket cam, substantially as set forth.

12. In a pull-rodpumping jack, a walking beam, a cam at one end thereof, a flexible member adapted to connect the walkingbeam to a pump-rod or the like, and means gfor actuating the cam in timed relation with the walking beam to keep the intermediate portion of the flexible member perpendicular during oscillatory movement of the walking beam, substantially as set forth.

In witness whereof, I have hereunto set ing on a fixed center, a device movable in a Hny hand at Washington. District of Columstraight line, a cam on the bar movable on a fixed axis, a flexible connection from said device passing about the periphery of said cam, and means for rotating the cam in bia, this22nd day of September, A. D. nineteen hundred and-twenty-four.

2| IUS n. nonnennnn. 

